How to specify the favicon image when generating it programmatically in Next.js

Question

With reference to the example in official documentation here, where do I specify the filename of the favicon image when generating it programmatically in Next.js?

// /app/icon.tsx
import { ImageResponse } from 'next/og'
 
// Route segment config
export const runtime = 'edge'
 
// Image metadata
export const size = {
  width: 32,
  height: 32,
}
export const contentType = 'image/png'
 
// Image generation
export default function Icon() {
  return new ImageResponse(
    (
      // ImageResponse JSX element
      <div
        style={{
          fontSize: 24,
          background: 'black',
          width: '100%',
          height: '100%',
          display: 'flex',
          alignItems: 'center',
          justifyContent: 'center',
          color: 'white',
        }}
      >
        A
      </div>
    ),
    // ImageResponse options
    {
      /* For convenience, we can re-use the 
         exported icons size metadata config to 
         also set the ImageResponse's width and    
         height. */
      ...size,
    }
  )
}

How is it generated? Have I understood this correctly?